Quarterly report pursuant to Section 13 or 15(d)

Share-based Compensation - Summary of Activity of Restricted Shares (Detail)

v3.21.1
Share-based Compensation - Summary of Activity of Restricted Shares (Detail)
 3 Months Ended
Mar. 31, 2021
$ / shares
shares
Restricted Stock [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Restricted Shares, Opening balance | shares 1,250,000
Number of Restricted Shares, Granted | shares 1,105,700
Number of Restricted Shares, Ending balance | shares 2,355,700
Weighted Average Grant Date Fair Value, Opening balance | $ / shares $ 15.28
Weighted Average Grant Date Fair Value, Granted | $ / shares 14.62
Weighted Average Grant Date Fair Value, Ending balance | $ / shares $ 14.97
Performance Condition Awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Restricted Shares, Granted | shares 713,700
Weighted Average Grant Date Fair Value, Granted | $ / shares $ 16.15
Shares, Non-vested Opening balance | shares 950,000
Shares, Non-vested Ending balance | shares 1,663,700
Weighted Average Grant Date Fair Value, Non-vested Opening balance | $ / shares $ 15.70
Weighted Average Grant Date Fair Value, Vested | $ / shares $ 15.89
Service Condition Shares [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares, Non-vested Opening balance | shares 200,000
Shares, Granted | shares 52,000
Shares, Non-vested Ending balance | shares 252,000
Weighted Average Grant Date Fair Value, Non-vested Opening balance | $ / shares $ 15.70
Weighted Average Grant Date Fair Value, Vested | $ / shares 15.79
Weighted Average Grant Date Fair Value, Granted | $ / shares $ 16.15
Market Condition Awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares, Non-vested Opening balance | shares 100,000
Shares, Granted | shares 340,000
Shares, Non-vested Ending balance | shares 440,000
Weighted Average Grant Date Fair Value, Non-vested Opening balance | $ / shares $ 10.45
Weighted Average Grant Date Fair Value, Vested | $ / shares 11.01
Weighted Average Grant Date Fair Value, Granted | $ / shares $ 11.17